test: logStream() behaves correctly like a good kiddo

Co-authored-by: Roberto Abdelkader Martínez Pérez <robertomartinezp@gmail.com>

internal/server/user/mux/handlerbuilder.go

@@ -20,6 +20,7 @@ import (
 	"bufio"
 	"log"
 	"net/http"
+	"io"
 	"os"
 
 	"github.com/google/uuid"
@@ -31,6 +32,7 @@ import (
 
 var spawner = spawn.Spawn
 var idGenerator = uuid.NewUUID
+var logHandler io.Writer = os.Stdout
 
 func handlerBuilder(route model.Route) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -77,7 +79,7 @@ func handlerBuilder(route model.Route) http.Handler {
 
 func logStream(handlerId string, streamName string, stream *os.File) {
 	defer stream.Close()
-	execLog := log.New(os.Stdout, "", log.Ldate|log.Ltime|log.LUTC|log.Lmicroseconds)
+	execLog := log.New(logHandler, "", log.Ldate|log.Ltime|log.LUTC|log.Lmicroseconds)
 	scanner := bufio.NewScanner(stream)
 	for scanner.Scan() {
 		execLog.Printf("%s %s: %s", handlerId, streamName, scanner.Text())

internal/server/user/mux/handlerbuilder_test.go

@@ -17,12 +17,15 @@
 package mux
 
 import (
+	"bytes"
 	"errors"
 	"io"
 	"net/http"
 	"net/http/httptest"
 	"reflect"
+	"strings"
 	"testing"
+	"time"
 
 	"github.com/google/uuid"
 
@@ -197,50 +200,32 @@ func TestHandlerBuilderRemovesHandlerWhenDone(t *testing.T) {
 	}
 }
 
-// func TestCreateLogMsgAdsPrefixInfo(t *testing.T) {
-// 	expected := "FOO"
+func TestHandlerBuilderLogToLogHandler(t *testing.T) {
+	data.Handlers = data.New()
+	route := model.Route{}
+	var got string
 
-// 	msg := createLogMsg(expected, bytes.Buffer{}, bytes.Buffer{})
+	logHandler = new(bytes.Buffer)
 
-// 	if msg.Prefix != expected {
-// 		t.Errorf("LogMsg doesn't contain expected Prefix. Expected: %s, got: %s", expected, msg.Prefix)
-// 	}
-// }
+	spawner = func(h *model.Handler, out io.Writer, er io.Writer) error {
+		out.Write([]byte("this is stdout"))
+		er.Write([]byte("this is stderr"))
 
-// func TestCreateLogMsgAdsStdOutInfo(t *testing.T) {
-// 	expected := "FOO\nBAR"
-// 	out := bytes.Buffer{}
-// 	out.WriteString(expected)
+		return nil
+	}
 
-// 	msg := createLogMsg("", out, bytes.Buffer{})
+	handlerBuilder(route).ServeHTTP(nil, nil)
 
-// 	if strings.Join(msg.Messages, "\n") != expected {
-// 		t.Errorf("LogMsg doesn't contain expected payload. Expected: %s, got: %s", expected, msg.Prefix)
-// 	}
-// }
+	// NOTE: logStream will write stdout and stderr contents eventually.
+	// We do not have any control the goroutines running logStream, thus we
+	// cannot use a synchronization primitive to wait for them.  Sorry.
+	time.Sleep(1 * time.Second)
 
-// func TestCreateLogMsgAdsStdErrInfo(t *testing.T) {
-// 	expected := "FOO\nBAR"
-// 	err := bytes.Buffer{}
-// 	err.WriteString(expected)
-
-// 	msg := createLogMsg("", bytes.Buffer{}, err)
-
-// 	if strings.Join(msg.Messages, "\n") != expected {
-// 		t.Errorf("LogMsg doesn't contain expected payload. Expected: %s, got: %s", expected, msg.Prefix)
-// 	}
-// }
-
-// func TestCreateLogMsgAdsStdOutAndStdErrInfo(t *testing.T) {
-// 	expected := "FOO\nBAR\nFOO BAZ"
-// 	out := bytes.Buffer{}
-// 	out.WriteString("FOO\nBAR\n")
-// 	err := bytes.Buffer{}
-// 	err.WriteString("FOO BAZ")
-
-// 	msg := createLogMsg("", out, err)
-
-// 	if strings.Join(msg.Messages, "\n") != expected {
-// 		t.Errorf("LogMsg doesn't contain expected payload. Expected: %s, got: %s", expected, msg.Prefix)
-// 	}
-// }
+	got = logHandler.(*bytes.Buffer).String()
+	if ! strings.Contains(got, "this is stdout") {
+		t.Errorf("Stdout not preserved. Actual: %+q", got)
+	}
+	if ! strings.Contains(got, "this is stderr") {
+		t.Errorf("Stderr not preserved. Actual: %+q", got)
+	}
+}